SWITCHGEAR Section 16. SECTION INCLUDES This Section includes service and distribution switchboards rated 600 V and less.

Transcription

1 PART 1 - GENERAL SECTION INCLUDES This Section includes service and distribution switchboards rated 600 V and less. RELATED SECTIONS Division 16 Section "Basic Electrical Materials and Methods" for general and installation materials and methods. Division 16 Section "Fuses." SUBMITTALS Product Data: For each product and component specified. Shop Drawings: For each switchboard. Show dimensioned plans and elevations, including required clearances and service space, component and device lists, and a single-line diagram showing main- and branch-bus current ratings and short-time and short-circuit ratings of switchboard. Include the following: Descriptive documentation of optional barriers specified for electrical insulation and isolation. Schedule of features, characteristics, ratings, and factory settings of individual protective devices. Wiring Diagrams: Details of wiring for power and control and differentiating between manufacturerinstalled and field-installed wiring. Samples: Of mimic bus with specified finish, for color selection. Qualification Data: For firms and persons specified in "Quality Assurance" Article. Reports of Field Tests and Observations: Certified by testing agency. Manufacturer field service report. Certificates for field testing agency, signed by Contractor, certifying that agency complies with requirements specified in "Quality Assurance" Article below. Report of Field Tests and Observations: Certified by testing agency. Maintenance Data: For switchboards to include in the maintenance manuals specified in Division 1. Include detailed manufacturer's written instructions on adjusting overcurrent protective devices. QUALITY ASSURANCE Testing Agency Qualifications: In addition to the requirements specified in Division 1 Section "Quality Control," an independent testing agency shall meet OSHA criteria for accreditation of testing laboratories, Title 29, Part 1907, or shall be a full-member company of the InterNational Electrical Testing Association. Testing Agency's Field Supervisor: Person currently certified by the InterNational Electrical Testing Association or National Institute for Certification in Engineering Technologies, to supervise on-site testing specified in Part 3. Listing and Labeling: Provide switchboard assemblies specified in this Section that are listed and labeled. The Terms "Listed" and "Labeled": As defined in the National Electrical Code, Article 100. Listing and Labeling Agency Qualifications: A "Nationally Recognized Testing Laboratory" as defined in OSHA Regulation Comply with NFPA 70. Comply with NEMA PB 2. Product Selection for Restricted Space: Drawings indicate maximum dimensions for switchboard equipment, including clearances between switchboard and adjacent surfaces and items. Switchboards having equal performance characteristics and complying with indicated maximum dimensions may be considered. DELIVERY, STORAGE, AND HANDLING Deliver in shipping splits of lengths that can be moved past obstructions in delivery path. Store so condensation will not occur on or in switchboards. Provide temporary heaters as required to avoid condensation. Handle switchboards according to NEMA PB 2.1. Use only factory-installed lifting provisions. PROJECT CONDITIONS Verify dimensions by field measurements. Determine suitable path for moving switchboard into place considering Project conditions. Verify clearance requirements. Locate switchboard to meet installation tolerances.

2 Revise locations and elevations from those indicated as required to suit Project conditions. PART 2 - PRODUCTS 2.1 MANUFACTURERS A. Manufacturers: Subject to compliance with requirements, provide products by the following: General Electric Co.; Electrical Distribution and Control Division. Square D Co. 2.2 MANUFACTURED UNITS A. Front-Connected, Front-Accessible Switchboard: Fixed, individually mounted main device, panel-mounted branches, and sections rear aligned. Ratings: Provide nominal system voltage, continuous main-bus amperage, and short-circuit current ratings as indicated on schedules. 2.3 FABRICATION AND FEATURES A. Enclosure Finish for Indoor Units: Factory-applied finish in manufacture's standard gray finish over a rust-inhibiting primer on treated metal surface. Barriers: Between adjacent switchboard sections. Service Conditions: NEMA PB 2, usual service conditions. Bus Transition and Incoming Line Pull Sections: Matched and aligned with basic switchboard. Hinged Front Panels: Allow access to breaker, metering, accessory, and blank compartments. Pull Box on Top of Switchboard: Include the following features: Adequate ventilation to maintain air temperature in pull box within same limits as switchboard. Removable covers forming top, front, and sides. Top covers at rear are easily removable for drilling and cutting. Bottom of insulating, fire-resistant material with separate holes for cable drops into switchboards. Cable supports arranged to facilitate cabling and adequate to support cables indicated, including those for future installation. Buses and Connections: 3 phase, 4 wire, except as otherwise indicated. Features as follows: Phase- and Neutral-Bus Material: Hard-drawn copper of 98 percent conductivity with feeder circuitbreaker line connections. Load Terminals: Silver-plated copper bus extensions equipped with compression connectors for outgoing circuit conductors 400 amp frame and above. Ground Bus: 1/4-by-2-inch (6-by-50-mm) minimum size, drawn-temper copper of 98 percent conductivity; equipped with pressure connectors for feeder- and branch-circuit ground conductors. For busway feeders, extend insulated equipment grounding cable to busway ground connection and support cable at intervals in vertical run. Contact Surfaces of Buses: Silver plated. Main Phase Buses, Neutral Buses, and Equipment Ground Buses: Uniform capacity the entire length of the switchboard main and distribution sections. Provide for future extensions from both ends. Isolation Barrier Access Provisions: Permit checking bus bolt tightness. Neutral Buses: 100 percent of the ampacity of the phase buses, except as indicated, and equipped with approved pressure connectors for outgoing circuit neutral cables. Bus extensions for busway feeder neutral bus is braced. 2.4 OVERCURRENT PROTECTIVE DEVICES A. Enclosed, Molded-Case Circuit Breaker: NEMA AB 1, handle lockable. Characteristics: Frame size, trip rating, number of poles, and auxiliary devices as indicated and interrupting capacity rating to meet available fault current. Application Listing: Appropriate for application, including switching fluorescent lighting loads or heating, air-conditioning, and refrigerating equipment. Circuit Breakers, 200 A and Larger: Trip units interchangeable within frame size. Circuit Breakers, 400 A and Larger: Field-adjustable short-time and continuous current settings. Current-Limiting Trips: Where indicated, let-through ratings less than NEMA FU 1, Class RK-5. Lugs: Compression lugs and power-distribution connectors for number, size, and material of conductors indicated. Shunt Trip: Where indicated.

3 Future Devices: Where indicated, equip compartments with mounting brackets, supports, bus connections, and appurtenances designed for overcurrent protective device types and ampere ratings indicated. 2.5 INSTRUMENTATION A. Instrument Transformers: NEMA EI 21.1, IEEE C57.13, and the following: Potential Transformers: Secondary voltage rating of 120 V and NEMA accuracy class of 0.3 with burdens of W, X, and Y. Current Transformers: Ratios as indicated and accuracy class and burden suitable for connected relays, meters, and instruments. Control Power Transformers: Dry type, mounted in separate compartments for units larger than 3 kv. Current Transformers for Neutral and Ground-Fault Current Sensing: Ground/neutral sensor current transformers located as indicated. Connect secondaries to ground overcurrent relays to provide selective tripping of bus tie and main breaker. Coordinate with feeder breaker ground-fault protection. Multifunction Digital Metering Monitor: Microprocessor-based unit suitable for 3- or 4-wire systems and with the following features: Switch selectable digital display of the following values with maximum accuracy tolerances as indicated: Phase Currents, Each Phase: Plus or minus 1 percent. Phase-to-Phase Voltages, 3 Phase: Plus or minus 1 percent. Phase-to-Neutral Voltages, 3 Phase: Plus or minus 1 percent. Megawatts: Plus or minus 2 percent. Megavars: Plus or minus 2 percent. Power Factor: Plus or minus 2 percent. Frequency: Plus or minus 0.5 percent. Megawatt Demand: Plus or minus 2 percent; demand interval programmable from 5 to 60 minutes. Accumulated Energy, Megawatt Hours: Plus or minus 2 percent. Accumulated values unaffected by power outages up to 72 hours. Mounting: Display and control unit flush or semiflush mounted in instrument compartment door. 2.6 CONTROL POWER A. Control Circuits: 120 V, supplied through secondary disconnect devices from control power transformer. Electrically Interlocked Main and Tie Circuit Breakers: 2 control power transformers in separate compartments with interlocking relays, connected to the primary side of each control power transformer at the line side of the associated main circuit breaker. 120-V secondaries connected through automatic transfer relays to effect a fail-safe automatic transfer scheme. Provide Kirk Key override. Control Power Fuses: Primary and secondary fuses for current-limiting and overload protection of transformer and fuses for protection of control circuits. Control Wiring: Factory installed, complete with bundling, lacing, and protection. Provide flexible conductors for No. 8 AWG and smaller, for conductors across hinges, and for conductors for interconnections between shipping units. 2.7 ACCESSORY COMPONENTS AND FEATURES A. Accessory Set: Include tools and miscellaneous items as required for overcurrent protective device test, inspection, maintenance, and operation. Portable Test Set: Arranged to permit testing of all functions of solid-state trip devices without removal from switchboard. Include relay and meter test plugs suitable for testing switchboard meters and switchboard class relays. Circuit-Breaker Removal Apparatus: Portable, floor-supported, roller-base, elevating carriage arranged for movement of breakers in and out of compartments for present and future breakers. 2.8 IDENTIFICATION A. Nameplates and label products are specified in Division 16 Section "Basic Electrical Materials and Methods." Compartment Nameplates: Engraved laminated-plastic or metal nameplate for each compartment, mounted with corrosion-resistant screws.

4 PART 3 - EXECUTION 3.1 EXAMINATION A. Examine elements and surfaces to receive switchboard for compliance with installation tolerances and other conditions affecting performance of switchboards. Do not proceed with installation until unsatisfactory conditions have been corrected. 3.2 INSTALLATION A. Install switchboards level and plumb as indicated, according to manufacturer's written instructions and NEMA PB 2.1. Support switchboards on concrete housekeeping bases, 4-inch (100-mm) nominal thickness. Temporary Lifting Provisions: Remove temporary lifting eyes, channels, and brackets and temporary blocking of moving parts from switchboard units and components. Operating Instructions: Frame and mount printed, basic operating instructions for switchboards, including control and key interlocking sequences and emergency procedures. Fabricate frame of finished wood or metal and cover instructions with clear acrylic plastic. Mount on the front of switchboards. Provide Framed and mounted One-Line of building electrical system near switchboard. 3.3 CONNECTIONS A. Connect switchboards and components to wiring systems and to ground as indicated and instructed by manufacturer. Tighten electrical connectors and terminals, including screws and bolts, according to manufacturer's published torque tightening values. Where manufacturer's torque values are not indicated, use those specified in UL 486A and UL 486B. 3.4 IDENTIFICATION A. Identify field-installed wiring and components and provide warning signs as specified in Division 16 Section "Basic Electrical Materials and Methods." Install compartment nameplates. 3.5 FIELD QUALITY CONTROL A. Prepare for acceptance tests as follows: Make insulation-resistance tests of each switchboard bus, component, and connecting supply, feeder, and control circuits. Make continuity tests of each circuit. Notify Owner of test. Testing Agency: Provide the services of switchboard vendor testing agency to perform specified acceptance testing. Acceptance Testing: After installing switchboards and after electrical circuitry has been energized, demonstrate product capability and compliance with requirements. Procedures: Perform each visual and mechanical inspection and electrical test stated in NETA ATS, Sections 7.1, , 7.9, 7.10, 7.11, and 7.14 as appropriate. Certify compliance with test parameters. Correct malfunctioning units on-site, where possible, and retest to demonstrate compliance; otherwise, remove and replace with new units, and retest. 3.6 ADJUSTING A. Set field-adjustable switches and circuit-breaker trip ranges as indicated. 3.7 CLEANING A. Upon completion of installation, inspect interior and exterior of switchboards. Remove paint splatters and other spots, dirt, and debris. Touch up scratches and mars of finish to match original finish. 3.8 DEMONSTRATION A. Startup Services: Engage a factory-authorized service representative to demonstrate and train Owner's maintenance personnel as specified below: To identify each switchboard location.

5 To instruct in function, operation, and maintenance of each component. To instruct in each distinct procedure and schedule related to servicing and preventive maintenance. 3.9 PROTECTION A. Temporary Heating: Apply temporary heat to maintain temperature according to manufacturer's written instructions. End of this Section